Triumph TR8 Brake Bulb Size

The Triumph TR8 brake light utilizes 1156 and P21W bulb sizes for the lighting system. Data for the specified vehicle covers the range from 1980 through 1981.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
1980-1981	1156

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W.	1156

Other Locations

Additional Notes

The 1156 is the sole brake bulb type listed for the Triumph TR8, covering the 1980-1981 model years.
The 1156 is an ANSI-standardized bulb used across the United States and Canada, operating at 12 volts with a 21-watt output.
As a single-filament bulb, the 1156 is dedicated to one lighting function, distinguishing it from dual-filament types that serve multiple roles such as combined brake and tail lighting.
The 1156 uses a BA15s bayonet base, a single-contact fitting where the "s" denotes a single pin, which is not interchangeable with the BA15d double-contact bayonet base used on dual-filament bulbs.